【作者】 莫伟；

【导师】 马少健；

【作者基本信息】 广西大学 ， 采矿工程， 2003， 硕士

【摘要】 随着易处理金矿资源的日益消耗，以高砷金矿为代表的难处理金矿资源的开发利用引起了世界范围内的广泛关注。我国高砷类难处理金矿资源储量丰富，分布广泛，开发利用这类金矿资源具有十分现实和长远的意义。广西贵港有较丰富的高砷金矿资源，目前主要生产浮选金精矿井作外销处理。为解决这一资源的就地处理，提高资源的开发利用价值，本论文以浮选金精矿的预处理为核心，研究了广西贵港高砷浮选金精矿的氰化浸出工艺。 高砷难处理金矿的金或以微细粒金镶嵌于砷黄铁矿或黄铁矿的裂隙中，或沉淀于硫化矿物晶粒间，或金粒以不溶体形式包裹于硫化矿物中。因此，氰化浸出前需要对其进行预处理，破坏包裹金的砷黄铁矿和黄铁矿，使金得以暴露。本文根据广西贵港难处理高砷金矿的性质特点，研究了多种预处理和氰化浸出工艺。主要包括：1、常规氰化浸金，考察了氰化钠用量、浸出时间及矿浆浓度对金浸出的影响。2、微波预处理氰化浸金，探讨了微波加热对矿物显微结构的影响，微波功率、微波处理时间、微波场中添加试剂等对预处理效果的影响及微波后细磨对浸金效果的影响。3、碱浸除砷预处理氰化浸出，考察了碱浸因素及氰化浸金因素对除砷及浸金效果的影响。4、联合工艺浸金，分别考察了微波—碱浸及细磨—碱浸联合预处理后对浸金效果的影响。 研究结果表明：广西贵港高砷金矿属典型的难处理金矿，在试验条件下，采用常规氰化浸出，金的最大浸出率为13.6％，在大多数条件下甚至根本无法浸出；微波加热预处理可以改善氰化浸出效果，但这种改善的效果受微波作用时间、微波作用强度、矿物细度及微波场中的添加剂等因素影响；碱浸是贵港难处理金精矿最有效的预处理方法，且氰化过程中添加氧化剂助浸可获得较高的金浸出率， 广西大学硕士学位论文：广西贵港高砷浮选金精矿氰化浸金试验研究金的最高浸出率可达72．7％；常温条件下，碱浸除砷预处理氰化浸金过程，金浸出率与砷脱除率呈正相关关系，提高温度将改变这种相互关系，大大降低砷的脱除率，并导致金无法浸出；采用微波一碱浸及细磨一碱浸联合工艺对含砷金矿进行预处理，在一定程度上可提高金的浸出率，但效果不明显。该研究结果对广西贵港高砷金矿氰化浸出工艺的设计具有重要的指导意义。更多还原

【Abstract】 With the increasingly exhausting of easily leachable gold ores, refractory gold ores have attracted extensive attention around the world. In China, the resource of refractory gold ores containing high arsenic is very abundant and extensively distributed. Therefore, it is practically meaningful to explore better use of refractory gold ores at the present and in the future of China. Guigang of Guangxi has rich refractory gold ores containing high arsenic, which are currently explored as flotation concentrate for sale. To make better use of the gold resource in Guigang for more extra value, the thesis presented the experimental study of cyanide leaching of the refractory ore focusing on the methods of the pretreatment of the gold concentrate.Generally the refractory gold ores of high arsenic can not be effectively leached because micro-granular gold is inserted in the cracks of arsenopyrite and pyrite, or precipitated on the interplanars of sulfides, in addition, some gold may have formed in unsolvable form in sulfides. Therefore, the pretreatment prior to gold leaching must be conducted, so that pyrite and arsenopyrite bundling gold are destroyed and gold is exposed to be leached easily. Based on the characteristics of the refractory gold concentrate of interest, our research looked into several process methods for the pretreatment and cyanide leaching of the concentrate. They are: 1) Traditional leaching process, in which the effects of NaCN dose, leaching time and solid concentration were discussed. 2) Microwave heating pretreatment /cyanide leaching, in which the effects of microwave heating on mineral microstructure, and those ofmicrowave power, heating time and adding alkaline material during microwave heating on leaching efficiency were studied. 3) Alkaline leaching pretreatment/ cyanide leaching, which detailed the effects of different conditions on the efficiency of alkaline leaching of arsenic and that of cyanide leaching of gold. Conjunction process of fine grinding with alkaline leaching was also investigated as the pretreatment of the cyanide leaching of the gold concentrate.A lot of conclusions were achieved from our experimental research as follows. Guigang gold concentrate is exactly a kind of typical refractory ore to which the traditional cyanide leaching was of very low efficiency, the highest gold leaching recovery being 12.4% and in most cases even no gold leaching taking place. Microwave pretreatment showed improvement of cyanide leaching, which was related to microwave power, heating time and addition of alkaline matters during microwave heating. The process of alkaline leaching pretreatment/cyanide leaching was verified to be the most effective process for gold extraction of Guigang gold concentrate. Meanwhile, the gold leaching recovery was directly related to arsenic removal level, and better result can be achieved by using some oxidizing agent during cyanide leaching after alkaline leaching pretreatment. Combination of fine grinding and alkaline leaching of arsenic could raise the gold leaching recovery to some extent, but the improvement was not very obvious. All these research results will provide a very meaningful instruction for the plant development of Guigang gold concentrate with cyanide leaching.更多还原